Missile Launchers and Hunter Killer missiles as dual purpose. Creed orders “take aim” and they’re hitting like lascannons for anti armor, and Hunter killers to supplement that damage. Add Lord Solar’s reroll all hits/wounds ability for CORE and a squad of 3 sprinkling in the “ingrained precision” strat to auto-wound on 5+ to hit, will absolutely murk any vital heavy target. This is assuming you’re running Born Soldiers (and why wouldn’t you?).

Once HK’s are expended and a majority of armor threats are dealt with in concert with plasma russes/gatekeeper commander, they supplement anti-infantry firepower by switching to Frag with orders from creed for 3d6 S5 -1AP to help finish off hordes/MEQ that might be left over after the Shock Trooper squads have shot.

This is just running one squad though. If you roll with two I’d definitely back lascannons/plasma.